Mats Engstrom’s gorgeous no-PCB nixie clock reads off one digit at a time.

It’s a clock made of a single IN-1 Nixie tube controlled by a ATMega8. The Mega8 directly controls 10 pcs of MPSA42 high voltage transistors for lighting up the filaments in in Nixie. It also generates the high voltage required for the tubes by a pwm output connected to a IRF520 N-FET and the usual inductor and fast recovery diode.